1974 horsepower

[badinfluenceRS]

i know the method for determining horsepower changed in like 1972 or so, anyone know if the factory horsepower rating for a 1974 oldsmobile would be at the crank or rear wheel hp? also anyone know how much hp the gm th400 tranny wastes?

[CDNFB]

Re: 1974 horsepower

I am of the belief that the manufacturers changed the method of hp rating from crank hp to rear wheel hp in 1972 in an effort to present lower HP numbers for insurance puposes. I remember reading this in an old Chiltons manual that explained the HP rating difference in comparing the 1971 or older F bodies to the 1972 or newer F-bodies. I don't have access to that manual anymore cause an old friend has it and he lives in another city. It was really old, like 1978 or something like that. Again, from memory the 1971 F-body with a 400 ci, 4bbl, auto trans was rated at 300 hp (If I remember) and in 1972 the same F-body (I know this one cause I have a 72 Formula 400) was rated at 250 hp. Using this as data, it looks like the drive train (THM 400 and 10 bolt rear end) consumed something like 50 horses at peak HP rpm. I think a good estimate on the THM 400 HP consumption would be in the area of 35 hp?

[Fireball27]

Re: 1974 horsepower

I am of the belief that the manufacturers changed the method of hp rating from crank hp to rear wheel hp in 1972 in an effort to present lower HP numbers for insurance puposes. I remember reading this in an old Chiltons manual that explained the HP rating difference in comparing the 1971 or older F bodies to the 1972 or newer F-bodies. I don't have access to that manual anymore cause an old friend has it and he lives in another city. It was really old, like 1978 or something like that. Again, from memory the 1971 F-body with a 400 ci, 4bbl, auto trans was rated at 300 hp (If I remember) and in 1972 the same F-body (I know this one cause I have a 72 Formula 400) was rated at 250 hp. Using this as data, it looks like the drive train (THM 400 and 10 bolt rear end) consumed something like 50 horses at peak HP rpm. I think a good estimate on the THM 400 HP consumption would be in the area of 35 hp?

Actually the change manufactures made was going from Gross HP ratings to Net HP ratings, they never gave numbers at the wheels.

Gross = The theoretical capability of the engine in a perfect world (more or less)

Net= HP after you calculate losses from all the various working parts of the engine.

Take a look at this wikipedia article, pretty intresting. http://en.wikipedia.org/wiki/Horsepower

[3.4 slow to go]

Re: 1974 horsepower

also anyone know how much hp the gm th400 tranny wastes?

a better question would be how much hp does it take to kill one ;)

[badinfluenceRS]

Re: 1974 horsepower

a better question would be how much hp does it take to kill one ;)

ha yea...me and my buddy are going to the track this spring and making some bets (mostly bragging rights) on whose car is going to be faster

So basically a 1974 factory hp rating is like a 1996 factory hp rating?

[Fireball27]

Re: 1974 horsepower

ha yea...me and my buddy are going to the track this spring and making some bets (mostly bragging rights) on whose car is going to be faster

So basically a 1974 factory hp rating is like a 1996 factory hp rating?

They both give you Net horsepower ratings, so yes.

[badinfluenceRS]

Re: 1974 horsepower

nice...i got his **** then

[Fireball27]

Re: 1974 horsepower

nice...i got his **** then

He has a 74 olds something i'm assuming?

[badinfluenceRS]

Re: 1974 horsepower

yea...he's got a 86 cutty w/ a 455 big block (230hp/300tq stock) 3 speed auto th400, but everything is kinda ghetto on it so i'm guessin his rwhp is no more than 210 hp w/ a few mods

[3.4 slow to go]

Re: 1974 horsepower

you positive it's stock? that torque rating sounds wrong, as my 77T/A w/the 400 had 325 on it, and it moved teh 3600+ beast pretty good

[badinfluenceRS]

Re: 1974 horsepower

ha i used to own it! G-body cutlass, pretty much stock, dual exhaust w/ glasspacks, and he's choking it off w/ a 650cfm edelbrock carb, non-posi w/ stock tires. It does have lots of tq...but it's not the TA motor, it's from a 74 cutlass

i'm only putting $5 down...but all my friends have doubted that a v6 could take that massive 455...so the bragging rights would be priceless

[Fireball27]

Re: 1974 horsepower

ha i used to own it! G-body cutlass, pretty much stock, dual exhaust w/ glasspacks, and he's choking it off w/ a 650cfm edelbrock carb, non-posi w/ stock tires. It does have lots of tq...but it's not the TA motor, it's from a 74 cutlass

i'm only putting $5 down...but all my friends have doubted that a v6 could take that massive 455...so the bragging rights would be priceless

If it can put the power down (which i'd seriously doubt, what with all that torque, and there being no lsd and stock tires) i'd say the cutlass would take it any day... but for $5 its worth it to see.

[badinfluenceRS]

Re: 1974 horsepower

we'll see this spring...